This invention relates to a molded plastic or metal screw-threaded device for firmly securing or anchoring objects into sandy beach surfaces as are encountered beside lakes and at the seashore. Once screwed into the sand, the device resists removal and thus provides a solid anchor for umbrellas, pet leashes, and the like.
In recent years, people have begun to devote more time to recreational pursuits, many of which involve being in or near water. Ocean and lakeside beaches have become increasingly popular destinations for active, sun-loving people. Such people eventually accumulate a variety of items they need for enjoyment of the beach environment. Such items often include beach umbrellas to afford protection from the sun's harmful rays, a variety of chairs and chaises for comfortable relaxation, inflatable floats and rafts for floating in the lake or ocean, volleyballs with nets and poles for exercise and competitive sport, and leashes for the family dog if one is allowed to accompany its family to the beach.
While people generally go to beaches to encounter sun and surf, one other element of nature is an almost constant accompaniment and must constantly be reckoned with. Wind can afford a cooling respite from the sun's heat but it can also wreak havoc on beach paraphernalia. Umbrellas, for example, are generally held in the sand by penetration of the tip of their poles several inches into the sand. Strong gusts of wind are frequently noted to lift an entire umbrella and move it a distance away to the irritation and potential danger of the owner and other beachgoers nearby. Floats, rafts, and webbed aluminum-frame chairs are light enough to be rendered airborne by strong beach gusts. Such unwanted interruptions could be prevented entirely through the use of a device to firmly anchor these objects into the sand. Likewise, beach volleyball nets, which must be held taut to be fully functional, need to be on poles that are held securely by ropes tied to tight anchors. Dogs could be more conveniently kept on leashes while owners sleep, play, or swim, if a secure place existed to attach the leash.
Various attempts have been made to provide ground-anchoring devices for ropes and poles. In U.S. Pat. Nos. 292,129 and 773,386, spiral-threaded rods which penetrate the ground are used to hold guy ropes and poles. In U.S. Pat. No. 292,129, the threaded rod is connected to a T-bar which forms a point for tying ropes and is solid steel, thus having no ability to receive and hold an umbrella. In U.S. Pat. No. 773,386, the threaded rod is not itself capable of holding a pole or umbrella but merely forms one of three anchors for a tripod-like steel apparatus to which poles can be attached. U.S. Pat. Nos. 2,103,948 and 2,209,504 and 4,819,904 all describe spiral-threaded umbrella tips that are attached permanently to the umbrella pole before its insertion into the ground, making the pole then capable of being screwed into the ground. In U.S. Pat. No. 2,103,948, the coneshaped hollow tip is attached to the umbrella pole by tightening a ring clamp. The assembled unit can then be turned into the ground. Similarly, U.S. Pat. No. 2,209,504 describes a tip that is permanently affixed to the umbrella pole by flat-headed wood screws before the unit is inserted into the soil. In U.S. Pat. No. 4,819,904, where the base of the conical threaded tip is intended to be hammered into the open end of a tubular umbrella pole, the unit once again must be assembled before the tip is inserted into the ground. None of these devices would allow the umbrella to be removed while the anchoring device remains in the ground to be used to hold other objects. U.S. Pat. Nos. 2,441,109 and 2,628,797 and 4,832,304 describe detachable spiral-threaded devices intended to hold umbrellas in the ground. In U.S. Pat. No. 2,441,109, the umbrella pole is retained by an undisclosed "attachment member" and the spiral threads are small and shallow, making its use practical only in hard soil. A separate attachment is required for screwing the unit into the ground. Likewise, U.S. Pat. No. 2,628,797 and 4,832,304 disclose screw-threaded umbrella-holding posts that have shallow spiral threads on the tip for use in hard soil. They both also disclose a cam mechanism of holding the umbrella pole secure. In the latter, moveable metal wings move this cam and also serve as the means of screwing the holder into the soil. Neither unit has any features that would allow for its being used to anchor other objects such as ropes or pet leashes. Also, neither of these devices allow penetration of the inserted umbrella even to the level of the threads and, with so few threads anyway, neither can offer more than minimal stability in hard soil and even less in sand.